Morton System Saver cabinet softeners (M20, M27, M30, MC30, M34, M45 / MSD series): quick sheet

In service, water enters the valve, goes down through the resin and returns up the center tube to the outlet, spinning a turbine with a magnet past a sensor on the way out. The board counts gallons. Using the hardness setting (plus 5 gpg for each 1 ppm of clear-water iron) and the model capacity, it decides when the resin is near exhaustion and schedules a recharge for the set time, 2:00 AM by default. Morton calls this demand-initiated regeneration.

A recharge is a series of rotor positions. A small 24 V DC motor turns a cam and gear, the gear turns a rotor against a ported disc, and a position switch tells the board when each position is reached. The manual's step-through order is fill, brine, backwash and fast rinse, then back to service. Because the brine tank is filled as the first step, little water normally stands in the salt tank between recharges.

Brine draw comes from the nozzle and venturi assembly on top of the valve: water forced through a small nozzle creates suction that pulls brine up the brine tube, through the brine valve, into the resin. Flow plugs in that assembly limit fill flow (0.1 gpm class) and backwash/drain flow (0.3 gpm class plug in the parts list). Dirt, iron or a misplaced gasket in the assembly gives hard water with a full salt tank or a tank that never fills.

Settings are kept through short outages; after a long outage the time flashes and must be reset while hardness and other settings stay. A Salt Efficiency option (shipped OFF) limits salt dose so the unit runs at 4,000 grains per pound or better. M34 and later models also have a salt-level setting read from a 0-8 scale on the brinewell, with a low-salt light at level 2 or below. The M45C Wi-Fi model reports to a phone app.